Earlier this year, in New York Fashion Week, Marc Jacobs launched a Popup store in which you could exchange tweets for Marc Jacobs Daisy goodies. Last week they brought the concept to London’s Covent Garden.

It’s very simple: share a tweet with #MJDaisyChain hashtag, and you collect a free deluxe sample of one of the Daisy family of fragrances.

Spending more time in the store is also a form of currency: you can get a manicure at a nail bar or even a cup of coffee. Or create a Vine to earn more currency and therefore goodies. Follower counts have no bearing on the value of the currency, meaning everyone can earn the same rewards.

Using tweets, vines and images as a marketing tool for the brand gains them visibility across networks and without doubt, a whole bunch of press coverage. The outlay of deluxe samples and a popup retail space must pay dividends: at the time of writing, 6795 images had been shared on Instagram and what appears to be countless hundreds of tweets.

Whilst I’ve seen campaigns of swapping Facebook likes for free drinks, the beginning of using social media updates as transactional processes marks an intriguing future for brands. It could be used as a tool to enable GWP or freebies in stores – why not reward your fans with a gift by asking them to do something as simple as tweet with a hashtag?